1066721 has 2 divisors, whose sum is σ = 1066722. Its totient is φ = 1066720.

The previous prime is 1066693. The next prime is 1066729. The reversal of 1066721 is 1276601.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 583696 + 483025 = 764^2 + 695^2 .

It is a cyclic number.

It is not a de Polignac number, because 1066721 - 2¹⁰ = 1065697 is a prime.

It is a super-2 number, since 2×1066721² = 2275787383682, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1066729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 533360 + 533361.

It is an arithmetic number, because the mean of its divisors is an integer number (533361).

2^1066721 is an apocalyptic number.

It is an amenable number.

1066721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1066721 is an equidigital number, since it uses as much as digits as its factorization.

1066721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 1066721 is about 1032.8218626656. The cubic root of 1066721 is about 102.1763257958.

The spelling of 1066721 in words is "one million, sixty-six thousand, seven hundred twenty-one".